xref: /linux/drivers/acpi/acpica/nsparse.c (revision e0643c4e9fdb2e77ab83ca596460e2c9c15728aa)
1 /******************************************************************************
2  *
3  * Module Name: nsparse - namespace interface to AML parser
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2016, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43 
44 #include <acpi/acpi.h>
45 #include "accommon.h"
46 #include "acnamesp.h"
47 #include "acparser.h"
48 #include "acdispat.h"
49 #include "actables.h"
50 #include "acinterp.h"
51 
52 #define _COMPONENT          ACPI_NAMESPACE
53 ACPI_MODULE_NAME("nsparse")
54 
55 /*******************************************************************************
56  *
57  * FUNCTION:    ns_one_complete_parse
58  *
59  * PARAMETERS:  pass_number             - 1 or 2
60  *              table_desc              - The table to be parsed.
61  *
62  * RETURN:      Status
63  *
64  * DESCRIPTION: Perform one complete parse of an ACPI/AML table.
65  *
66  ******************************************************************************/
67 acpi_status
68 acpi_ns_one_complete_parse(u32 pass_number,
69 			   u32 table_index,
70 			   struct acpi_namespace_node *start_node)
71 {
72 	union acpi_parse_object *parse_root;
73 	acpi_status status;
74 	u32 aml_length;
75 	u8 *aml_start;
76 	struct acpi_walk_state *walk_state;
77 	struct acpi_table_header *table;
78 	acpi_owner_id owner_id;
79 
80 	ACPI_FUNCTION_TRACE(ns_one_complete_parse);
81 
82 	status = acpi_get_table_by_index(table_index, &table);
83 	if (ACPI_FAILURE(status)) {
84 		return_ACPI_STATUS(status);
85 	}
86 
87 	/* Table must consist of at least a complete header */
88 
89 	if (table->length < sizeof(struct acpi_table_header)) {
90 		return_ACPI_STATUS(AE_BAD_HEADER);
91 	}
92 
93 	aml_start = (u8 *)table + sizeof(struct acpi_table_header);
94 	aml_length = table->length - sizeof(struct acpi_table_header);
95 
96 	status = acpi_tb_get_owner_id(table_index, &owner_id);
97 	if (ACPI_FAILURE(status)) {
98 		return_ACPI_STATUS(status);
99 	}
100 
101 	/* Create and init a Root Node */
102 
103 	parse_root = acpi_ps_create_scope_op(aml_start);
104 	if (!parse_root) {
105 		return_ACPI_STATUS(AE_NO_MEMORY);
106 	}
107 
108 	/* Create and initialize a new walk state */
109 
110 	walk_state = acpi_ds_create_walk_state(owner_id, NULL, NULL, NULL);
111 	if (!walk_state) {
112 		acpi_ps_free_op(parse_root);
113 		return_ACPI_STATUS(AE_NO_MEMORY);
114 	}
115 
116 	status = acpi_ds_init_aml_walk(walk_state, parse_root, NULL,
117 				       aml_start, aml_length, NULL,
118 				       (u8)pass_number);
119 	if (ACPI_FAILURE(status)) {
120 		acpi_ds_delete_walk_state(walk_state);
121 		goto cleanup;
122 	}
123 
124 	/* Found OSDT table, enable the namespace override feature */
125 
126 	if (ACPI_COMPARE_NAME(table->signature, ACPI_SIG_OSDT) &&
127 	    pass_number == ACPI_IMODE_LOAD_PASS1) {
128 		walk_state->namespace_override = TRUE;
129 	}
130 
131 	/* start_node is the default location to load the table */
132 
133 	if (start_node && start_node != acpi_gbl_root_node) {
134 		status =
135 		    acpi_ds_scope_stack_push(start_node, ACPI_TYPE_METHOD,
136 					     walk_state);
137 		if (ACPI_FAILURE(status)) {
138 			acpi_ds_delete_walk_state(walk_state);
139 			goto cleanup;
140 		}
141 	}
142 
143 	/* Parse the AML */
144 
145 	ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
146 			  "*PARSE* pass %u parse\n", pass_number));
147 	status = acpi_ps_parse_aml(walk_state);
148 
149 cleanup:
150 	acpi_ps_delete_parse_tree(parse_root);
151 	return_ACPI_STATUS(status);
152 }
153 
154 /*******************************************************************************
155  *
156  * FUNCTION:    acpi_ns_parse_table
157  *
158  * PARAMETERS:  table_desc      - An ACPI table descriptor for table to parse
159  *              start_node      - Where to enter the table into the namespace
160  *
161  * RETURN:      Status
162  *
163  * DESCRIPTION: Parse AML within an ACPI table and return a tree of ops
164  *
165  ******************************************************************************/
166 
167 acpi_status
168 acpi_ns_parse_table(u32 table_index, struct acpi_namespace_node *start_node)
169 {
170 	acpi_status status;
171 
172 	ACPI_FUNCTION_TRACE(ns_parse_table);
173 
174 	acpi_ex_enter_interpreter();
175 
176 	/*
177 	 * AML Parse, pass 1
178 	 *
179 	 * In this pass, we load most of the namespace. Control methods
180 	 * are not parsed until later. A parse tree is not created. Instead,
181 	 * each Parser Op subtree is deleted when it is finished. This saves
182 	 * a great deal of memory, and allows a small cache of parse objects
183 	 * to service the entire parse. The second pass of the parse then
184 	 * performs another complete parse of the AML.
185 	 */
186 	ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "**** Start pass 1\n"));
187 
188 	status = acpi_ns_one_complete_parse(ACPI_IMODE_LOAD_PASS1,
189 					    table_index, start_node);
190 	if (ACPI_FAILURE(status)) {
191 		goto error_exit;
192 	}
193 
194 	/*
195 	 * AML Parse, pass 2
196 	 *
197 	 * In this pass, we resolve forward references and other things
198 	 * that could not be completed during the first pass.
199 	 * Another complete parse of the AML is performed, but the
200 	 * overhead of this is compensated for by the fact that the
201 	 * parse objects are all cached.
202 	 */
203 	ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "**** Start pass 2\n"));
204 	status = acpi_ns_one_complete_parse(ACPI_IMODE_LOAD_PASS2,
205 					    table_index, start_node);
206 	if (ACPI_FAILURE(status)) {
207 		goto error_exit;
208 	}
209 
210 error_exit:
211 	acpi_ex_exit_interpreter();
212 	return_ACPI_STATUS(status);
213 }
214